Summary of Significant Accounting Policies (Details 3) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Apr. 26, 2015	Apr. 27, 2014	Apr. 28, 2013
Summary of Significant Accounting Policies
Rooms	$ 9,397	$ 8,956	$ 8,979
Food and beverage	68,825	65,287	60,557
Other	527isle_CostOfComplimentaryServicesOther	519isle_CostOfComplimentaryServicesOther	602isle_CostOfComplimentaryServicesOther
Total cost of complimentary services	78,749isle_CostOfComplimentaryServices	74,762isle_CostOfComplimentaryServices	70,138isle_CostOfComplimentaryServices
Deferred financing costs	19,075us-gaap_DeferredFinanceCostsNet
Advertising
Advertising costs	$ 34,918us-gaap_AdvertisingExpense	$ 35,480us-gaap_AdvertisingExpense	$ 32,668us-gaap_AdvertisingExpense

Represents the total cost services given to guests without charge.

No definition available.

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- Definition

Represents the estimated cost of food and beverage offered to guests without charge.

+ References

No definition available.

+ Details

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- Definition

Represents the cost of accommodations furnished to guests without charge.

+ References

No definition available.

+ Details

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- Definition

Represents the cost of other services given to guests without charge.

+ References

No definition available.

+ Details

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Namespace Prefix:	isle_
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- Details

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- Definition

Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 720

-SubTopic 35

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6420018&loc=d3e36677-107848

+ Details

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- Definition

For an unclassified balance sheet, the carrying amount (net of accumulated amortization) as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings over the life of the debt instruments to which such costs pertain.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28555-108399

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.17)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 17

-Article 5

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